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La demanda de alimentos a nivel mundial ha mantenido un constante crecimiento, y en particular los productos perecederos que requieren de manejo especializado para asegurar su inocuidad al llegar con el consumidor final. La cadena de frío es una importante herramienta para lograr este objetivo. Sin embargo, existen problemas en los distintos eslabones que pueden afectar la calidad del producto. La venta al menudeo resulta ser un eslabón débil, por lo que la cadena de frío necesita ser monitoreado para asegurar que no se presenten fluctuaciones de temperaturas que afecten negativamente la calidad e inocuidad de los alimentos. En esta investigación, se evaluó la gestión de cadena de frío de carne de res vendida en cuatro supermercados del estado de México, considerando aquellos que utilizan refrigeradores de tipo abierto. Se registró la temperatura superficial del producto localizado en diferentes posiciones del refrigerador. Los datos obtenidos se analizaron con un modelo mixto con mediciones repetidas en el tiempo bajo un diseño completamente al azar. Se determinó que dos de los cuatro supermercados, presentaron problemas de gestión de la cadena de frío durante los meses evaluados, incumpliendo lo estipulado en la norma NOM-213-SSA1-2018. Esto representa un riesgo para el consumo humano, por la posible proliferación de microorganismos causada por el aumento de temperatura, además de reducir la vida de anaquel y posterior desperdicio de alimentos, generando pérdidas económicas.

Haemonchus contortus is a nematode parasite that causes anaemia and affects the health of sheep. The mean corpuscular haemoglobin concentration (MCHC) is an excellent indicator to detect anaemia that could help to characterize resistant or susceptible lambs to gastrointestinal nematodes. The aim of this study was to evaluate the predictive value of MCHC in detecting changes in red blood cells and their relation to anaemia in lambs re-infected with H. contortus. An analysis of information was performed using 24 Pelibuey lambs previously infected in grazing, dewormed and experimentally re-infected with H. contortus. At the first haematological sampling (admission) the lambs were classified based on MCHC quartiles (Q). Subsequently, the lambs were housed for 56 days. Blood samples were taken every seven days to determine the haematological parameters using an impedance haematological instrument. Confidence limits were constructed with the records of the lambs that recovered their haematological parameters. Each quartile was analysed as a treatment in a repeated measures design over time. To know the optimal combination of sensitivity and specificity of MCHC to detect anaemia a curve of receiver operating characteristic (ROC) curve and the cut-off values were evaluated. In quartile 4 (Q4), lambs showed the highest faecal egg count (FEC, 764 eggs/g of faeces), mean corpuscular haemoglobin (17.0 pg) and MCHC (54.6 g/dL). This group also presented the lowest RBC values (5.8 × 106/mL), haematocrit (HCT, 18.3%), total plasma protein (5.7 g/dL), and HGB (9.7 g/dL). The optimal point of MCHC with ROC curve was 42.4 (sensitivity 88.2% and specificity 86.5%); the area under the curve was 0.91 (CI 95%, 0.86–0.96). These results are related to the haematological effects caused by H. contortus in susceptible lambs. In conclusion, the highest FEC and lower HCT in Q4 are important elements of the haematological damage caused by H. contortus and could identify susceptible lambs.

The aim of the study was to evaluate the in vitro nematicide activity of the allspice (Pimienta dioica) and oregano (Origanum vulgare) essential oils (EOs) on eggs and larvae of gastrointestinal nematodes (GIN) from ruminant. The EOs were obtained by hydro-distillation of previously dehydrated plant material. In the in vitro evaluation, the egg hatching and larval mobility of Haemonchus contortus and Cooperia spp. of sheep and cattle, respectively, were determined. EOs at concentrations of 20.2–252.3 µg µL(−1) with serial dilutions were used, also a negative control (distilled water + Tween 20) and Thiabendazol (77 µg µL(−1)) and Levamisole (120 µg µL(−1)) as a positive control to eggs and larvae, respectively, were placed on microplates. The results were analyzed with the PROBIT procedure. PPEO showed ovicidal effect in vitro test, with lethal doses 99 (LD(99)) of 0.56–4.19 µg µL(−1), while oregano essential oil (OREO) was shown to be a larvicidal activity with doses of LD(99) of 0.15–6.60 L(−1). The results confirm that P. dioica and O. vulgare EOs have ovicidal and larvicidal capacity against GIN in vitro test.

In this study, lactic acid bacteria (LAB) strains were isolated from ground beef, and it was analyzed if they have any effect on the growth of two reference bacteria (Salmonella sp. and Escherichia coli). It was found that five isolates showed an inhibitory effect in both reference bacteria by spot at the lawn assay. These bacteria were selected to perform growth kinetics in co-culture to determine if they modify the growth parameters of the reference bacteria. Subsequently, LAB cultures and three treatments (crude extract, thermally treated and thermally treated with neutral pH) of cells free supernatants (CFS) were screened by the agar well diffusion assay. In co-culture, selected LAB altered the growth rate and reduce the maximum population of both reference bacteria. While, LAB cultures and CFS also showed antimicrobial activity, and there was no significant difference among CFS treatments. LAB isolated from ground beef showed an antimicrobial effect against the reference bacteria that could be used for meat biopreservation purposes.

The objective of the study was to determine the parasitological and immune response in horses naturally re-infected with gastrointestinal nematodes (GIN) after an- thelmintic treatment in the humid tropic of Mexico. The study was conducted in Tenosique, Tabasco, Mexico. A total of 30 horses were sampled monthly for nine months. Fecal samples were obtained to determine the number of nematode eggs per gram (EPG) of feces. Stool cultures were performed to obtain and identify infective larvae (L3) genera. Blood samples were also obtained to determine the packed cell volume (PCV), the total plasma protein (TPP), and the differential leukocyte count (DLC). Serum enzyme-linked immunosorbent assays (ELISA) were performed to determine IgA levels against adult cyathostomins and Strongylus nematode antigen. The analyses considered the age and gender of the horses, and the season (Cold, rainy and dry). The number of EPG and TPP were higher in females (1224 ± 1269 and 7.6 ± 0.6 gdL−1, respectively) than males (623 ± 671 and 7.4 ± 0.5 gdL−1, respectively), and no differences were observed with animal age (p > 0.05). The number of EPG increased in the rainy season. The main nematodes involved were of the subfamily Cyathostominae (97.4%) and to a lesser degree of species Strongylus equinus, S. edentatus, S. vulgaris, and Oxyuris equii. The season affected the leukocytes, neutrophils, and lymphocytes counts but not eosinophils. Variables such as gender, animal age, and environmental conditions are important elements for a diagnosis of GIN and the application of treatments for its control.

A new device (Chapingo device) to deposit semen at the base of the uterine horns of cattle was developed at Universidad Autonoma Chapingo, Mexico. Nine Holstein heifers were inseminated by transvaginal laparoscopy, using a laparoscope for cattle and the Chapingo device. A dose of sexed semen (2.1 × 106 spermatozoa) was deposited at the base of the uterine horn ipsilateral to the ovary where the preovulatory follicle was identified. Insemination was achieved in all the heifers, taking on average 13.7 ± 3.1 min per animal. In all cases, it was possible to see both ovaries, the base of the uterine horns and the oviducts. After the procedure, none of the heifers showed any type of complications such as haemorrhage, adhesions or trauma. On days 21 and 22 after insemination, four of the nine heifers (44.4%) returned into oestrus; on day 30 after insemination, one heifer was found to be pregnant by ultrasound. The results show the feasibility of generating pregnancies by transvaginal laparoscopy in heifers inseminated with sexed semen.

This is the first report about anthelmintic resistance (AR) in hair sheep farms determined in a sub-humid tropical climate, in an area known as Huasteca Potosina, Mexico. Faecal egg count reduction tests (FECRT) and egg hatch in vitro tests were conducted to identify the level of AR against benzimidazole (BZ) in parasitic gastrointestinal nematode (GIN) populations. An allele-specific polymerase chain reaction (AS-PCR) was performed to obtain a 250 bp band, indicating resistance, and a 550 bp band, indicating susceptibility to BZ. Macrocyclic lactones (ML) and imidazothiazole (IMZ) drugs were also tested with the FECRT. A PROBIT analysis was conducted using SAS to determine the 50% lethal doses (LD50) of the drugs according to the egg hatch in vitro test. Resistance to BZ and ML was found on all farms (0–70% effectiveness), whereas the susceptibility of nematodes to IMZ was detected with the FECRT (93–100% effectiveness). The LD50 was higher than the discriminating dose (0.1 μg ml−1) for BZ and confirmed AR to this anthelmintic; we also confirmed a high AR frequency with AS-PCR. Therefore, we suggest that strategic deworming should be performed to avoid the development of resistance to imidazothiazole.

World trade challenges food safety and quality. This chapter is focused on a deep insight into the performance of potential hazards on food safety and biosecurity associated with foodstuffs. This detailed framework provides definitions, potential risks, prevention, antimicrobial resistance, epidemiology, and the surveillance of each potential hazard associated with agro-chemical and veterinary drug residues, genetically modified organisms, heavy metals, microbial pathogens, naturally occurring toxicants, parasitic organisms, persistent organic pollutants, physical contaminants and adulterants, prions, and zoonotic diseases. Biosecurity aspects are discussed and policy and regulatory frameworks for analyzing and managing relevant health risks, and those associated with the environment. It covers safety and risk management in the food supply chain, traceability and recalls, on-farm biosecurity management and animal hygiene as well as joint risk management tool release of living modified organisms and their products. Furthermore, inherent elements according to a range of economic factors are included on both topics as well. It also provides future challenges on food control and biosecurity.

This paper aims to identify how cold chain management is provided throughout the transportation of perishable food, as well as the role of the experience and working conditions of drivers in perishable food transportation. It draws on survey data collected from Mexican perishable food carriers with headquarters in six major cities. The results show the characteristics of the vehicles used to transport perishable food by Mexican carriers and the cooling technologies utilized by vehicles carrying different types of meat. Further, the results elucidate the work experience and training of drivers handling perishable products and problems related to cold chain transportation as a major strength, while weaknesses were those reported with loading delays and lack of widespread wireless system implementation for temperature registration. It also provides one of the first pieces of information on Mexico’s foodstuff transportation system, with the aim of designing strategies for better cold chain tracking during transportation, as a key factor in food waste reduction. It is necessary to incorporate a greater number of participants from other geographical areas of the country in order to get a more detailed overview and to determine similarities and differences between regions. This study provides baseline information for the development of appropriate logistics strategies in cold chain management.

Body weight in different mammalian species influences reproductive potential. The aim of the present study was to determine the relationship of body weight at the time of semen collection with libido, seminal characteristics and number of semen doses for artificial insemination (AI) in New Zealand White mature fertile male rabbits. Data came from 728 semen collections of 14 rabbits, 15-months of age that were sexually experienced with proven semen quality and fertility. Semen collection was performed twice a week with two ejaculates at each collection time and lasted 14 weeks. A second ejaculation was collected at 1-2h after the first. Data from each male from first and second ejaculates from 1 day of semen collection throughout the trial were averaged (n=324) and partial correlation coefficients and regression equations were estimated to describe the relationship of male body weight to ejaculation reaction time and 12 semen and sperm characteristics. As body weight increased there was a linear (P0.05) increase in reaction time, abnormal sperm with an intact membrane and abnormal sperm with a damaged membrane and a linear (P0.05) decrease in semen volume, sperm concentration per ejaculate, normal sperm with an intact membrane, number of normal motile sperm with an intact membrane and suitable semen doses for AI. Body weight of the mature male rabbit at semen collection had some influence on libido, semen and sperm characteristics, with a general trend toward a lesser reproduction potential as body weight increases.

Requirements of hazard analysis and critical control points (HACCP) are becoming essential for international trade in food commodities as a safety assurance component. This research reports the level of the adoption of ISO 9000 and the HACCP system by Federal Inspection Type (TIF) pork-exporting enterprises. Implementation and operating costs are reported as well as the benefits involved in this food industry process. In Mexico, there are 97 companies classified as TIF enterprises, and 22 are registered as exporters of processed pork with the National Services for Safety and Quality and Animal Health of the Secretariat of Agriculture, Livestock, Rural Development, Fisheries and Food. Surveys were administered to 22 companies, with a 95.2% response rate. Enterprise characteristics were evaluated, as well as their operating activities. Fieldwork consisted of administering structured questionnaires to TIF exporters. All the surveyed enterprises had implemented HACCP, whereas the ISO 9000 regulation was applied in only 30%. Of total production, 75% is exported to 13 countries, and 25% goes to the Mexican market niche. Results indicate that the main factors for adopting HACCP are related to accessibility to international markets, improving quality, and reducing product quality audits by customers. The results also indicated that staff training was the most important issue. Microbiological testing was the highest cost of the operation. The main benefits reported were related to better access to international markets and a considerable reduction in microbial counts. This study shows the willingness of Mexican pork processors to implement food safety protocols for producing safe and quality products to compete in the international food trade.

International trade scrutinises food safety practices and procedures, and food businesses have to review their safety procedures more rigorously. HACCP is increasingly relied on to ensure food safety in both meat-producing and meat-processing enterprises. The objective of this study was to compare incentives, costs, difficulties and benefits of Chinese and Mexican meat-exporting enterprises related to food safety management systems implementation. A questionnaire was applied to identify the main factors involved in HACCP implementation. Data were collected among 32 Chinese and 42 Mexican companies, and analysed using the SAS package. The implementation of the HACCP system was filled out in all exporting meat industries. The results indicated that the major incentives were related to improving product quality for both countries, whilst improving control of the process was the first motivation in the Chinese industry and access to new foreign markets was the first motivation in the Mexican one. In addition, both countries’ industries reported that staff training was the most important implementing cost, while product testing was the major operating cost. The difficulties found during HACCP implementation and operation activities were associated with availability of personnel for other tasks for China and costs of certification for Mexico. The reported benefits were relevant for the two countries, due to the ability to reduce microbial counts and increased access to foreign and domestic markets. A better understanding of the costs and benefits associated with HACCP systems could be helpful and is necessary in every segment of the food chain in every sector of domestic and international markets in order to assure food quality and safety.

Retail packages (N = 1004) containing fresh US beef in display cases in five cities across three regions of Mexico were surveyed for cut types, cutting styles, fat thickness measurements, marbling scores, and USDA Quality Grades to gain an overview of fresh US beef in Mexican retail markets. Data were analyzed to generate frequency distributions and examine the effect of city, geographical region, store chain, and socio-economic status of the targeted clientele on type, cutting style, fat measures and quality of beef cuts of US origin. Top round, bottom round and knuckle were the most common cut types. Milanesa-type slice and “bistec” (steak for grilling) were the predominant cutting styles. Over 95% of the retail cuts were trimmed to ˂3.2 mm or less of external fat. Most cuts were USDA Select (74.5%) and USDA Choice (24.5%). External fat thickness and marbling score differed among cities and store chains (P

The objective was to study the yearly and monthly trends for the number of positive samples (NPS) and the infestation level (IL) of Varroa destructor in honeybees (Apis mellifera). The study was carried out from 2002 to 2006 at the SAGARPA Bee Identification and Diagnosis Laboratory. Mite detection was performed using the De Jong procedure for V. destructor. Estimates of annual and monthly trends for NPS and IL were obtained through regression analysis. The monthly average for NPS was 47.6 ± 49.3 NMP, with the range varying from 0 to 248 samples per month. The annual trend (-5.69 ± 4.48) for the increase in the number of bee samples tested positive for V. destructor was not different from zero (P = 0.2087). The monthly trend from January to December was 0.91 ± 1.7 (P = 0.6024). The average IL in the positive samples was 3.27 ± 2.6 %, while the monthly average ranged from 0 to 10.06 %. The average annual rate of increase in IL was 0.34 ± 0.23 % (P = 0.2494). The average monthly rate of increase, from January to December, was -0.17 ± 0.1 % (P = 0.1194). The NPS with V. destructor and the IL showed no significant increases for the period studied. There was no effect of seasonality on NPS and IL.

Traceability in the Mexican dairy processing industry was studied to understand drivers behind its implementation. A questionnaire was applied to 33 plants. Data were analyzed using univariate and tabulate procedures of SAS. All plants operated Hazard Analysis and Critical Control Points, ISO or other food safety system. The 85.7% of respondents had traceability operating. Motivations to implement traceability were legal responsibility, and risks/worries of product recall; the enterprise problems were lack of supplier and customer feedback, and ability to manufacture new products; among benefits were regulatory requirements met, enterprises' image and reduced product recall/withdrawal. Economic and market reasons are important for traceability systems of the Mexican dairy processing industry. PRACTICAL APPLICATIONS Given the importance of traceability in domestic and international markets, especially the quality of raw materials used in the food processing sector, this study reports the first baseline information for the Mexican dairy processing sector. The results will allow improving the traceability systems in order to have a better market positioning both in the domestic and international markets. A higher number of Mexican suppliers could be incorporated into this food chain, because the most important quality requirements to be met will be available for this group of enterprises that process dairy products. Another impact is to determine the consumer preference, and a better positioning in foreign markets that require traceability systems in dairy products.

Female exposure of males could be a low-cost biostimulation option that benefits AI in commercial rabbit operations by improving buck rabbits reproductive performance. The objective of the study was to evaluate exposure of buck rabbits to females as a biostimulation option to improve reproductive potential. Treatments were: exposure (biostimulated) or not (control) of bucks to does. Bucks were New Zealand White, 15-month-old, sexually experienced and fertile. Experimental design was completely random with nine replications, experimental unit was one buck. Doe exposure was permanent using replacement pubertal does housed in an adjacent wire-mesh cage and changed for new ones every other week. Semen collection lasted 14 weeks (late winter and early spring) twice a week with two ejaculates at each collection. Analyses of variance were under a mixed model: treatments, ejaculate number and season were fixed and rabbit random effects and buck weight at each collection as covariable. Biostimulated bucks showed greater (P0.05) reproductive potential due to: 7% lesser reaction time (greater libido); and increased semen volume (40%), sperm motility (29%), sperm per ejaculate (31%), normal alive motile sperm (65%) and number of semen doses (64%). Semen characteristics differed by season in control bucks but not in doe exposed bucks (treatment × ejaculate number, P0.05). Reproductive potential in spring was greater (P0.05) than in winter in both treatments. Doe exposure is a biostimulation method that improves sexual drive and sperm production and quality of buck rabbits.

"Los objetivos fueron evaluar el efecto de la aplicación de gonadotropina coriónica humana (hCG) el día (d) 7 después de la inseminación en la formación de un cuerpo lúteo accesorio (CLA), la concentración de progesterona (P4) en plasma y la fertilidad. Se usaron 204 vacas Holstein lactantes, asignadas aleatoriamente a dos tratamientos: En el T1 (n=102), las vacas recibieron 1.000 UI de hCG y en el T2 (n=102), las vacas recibieron 2 mL de solución salina. Los d 7 y 14 después del servicio se tomaron muestras de sangre de la vena yugular para determinar la concentración de P4 en plasma y el d 14 se revisaron los ovarios por ultrasonido para evaluar la incidencia de un CLA, su diámetro, perímetro y área. La P4 se determinó mediante radioinmunoanálisis. El diagnóstico de gestación se realizó por ultrasonido 35 y 60 d después del servicio, en vacas que no retornaron a estro. La incidencia de CLA y el porcentaje de gestación fueron analizados mediante regresión logística, y el diámetro, perímetro, área y concentración de P4 con modelos mixtos. La concentración de P4 en los d 7 y 14 después de la inseminación fue similar (P>0,05) entre tratamientos. La incidencia de CLA fue mayor (P0,05) en el diámetro vertical, perímetro y área del CLA entre T1 y T2 (17,1 ± 0.3 vs 17,4 ± 0,8 mm; 65,9 ± 1.3 vs 66,2 ± 3,4 mm; y 299,9 ± 10,9 vs 293,9 ± 29,7 mm2, respectivamente) ni en el porcentaje de gestación entre tratamientos el d 35 (53,9 vs 43,1%) y 60 (43,1 vs 35,3%), respectivamente. En conclusión, la aplicación de hCG el d 7 después de la inseminación induce la formación de CLA, sin afectar sus características morfológicas, la concentración de P4 ni la fertilidad de vacas Holstein."

The effect of six genotypes (Zebu = Z, European Brown Swiss = EBS, Holstein = H, Z × EBS, Zebu × American Brown Swiss = ABS, Z × ABS, Z × H) on carcass and meat characteristics of young bullocks finished under feedlot conditions was tested. The Z × ABS bullocks had the highest (P = 0.001) average daily gain. The highest (P = 0.017) final liveweight was observed with Z × ABS > EBS > H genotypes. The ribeye area was larger (P = 0.012) for EBS bullocks. Both H and EBS bullocks had lowest (P = 0.001) physiological maturity; although the H bullocks had higher (P = 0.006) pelvis and heart fat values. The best (P = 0.014) conformation was obtained with the Z × ABS and Z × EBS genotypes. The greatest amount of marbling (P = 0.001) was obtained with the H genotype. In general, the crossbred genotypes showed better feedlot performance and carcass characteristics, and it seems that Holstein breed could have a an advantage from the marbling score point of view.

El objetivo del presente trabajo fue evaluar la eficiencia del lí- quido folicular equino (LFE) adicionado en un protocolo de sin- cronización de estros en ovejas Criollas. Se sincronizaron 79 ovejas multíparas con un peso vivo promedio de 37±7,1 kg usando esponjas intravaginales conteniendo 20 mg de Acetato de Fluorogestona (FGA); diez días (d) después de la inserción se inyectaron vía intramuscular, 0,075 mg de prostaglandinas (D-cloprostenol). El d 11, los animales recibieron 0 (T1; n=20), 2 (T2; n=20), 3 (T3; n=20) ó 4 (T4; n=19) mL de LFE por vía in- tramuscular. El LFE se obtuvo aspirando folículos mayores de 20 mm de diámetro, centrifugado a 952 g por 15 minutos (min) y fue almacenado a -5°C hasta su utilización. Las espon- jas se retiraron el d 12 y 24 horas (h) después se inició la de- tección de estros. Las ovejas fueron inseminadas con semen fresco por laparoscopía 20 h después del inicio del estro, utili- zando 100 x 10 estros (IE, %), tiempo de inicio al estro (TIE, h), número de fo- lículos preovulatorios (NFP), diámetro del folículo preovulatorio (DFP, mm), tasa ovulatoria (TO), diámetro del cuerpo lúteo (DCL), tasa de gestación (TG) y prolificidad (P). Los datos se analizaron con pruebas de Ji-cuadrado y ANOVA. Se encon- traron diferencias (P0,05) en TIE entre T1 y T3 (55,95 ± 2,18 vs. 64,60 ± 2,18), en TO entre T1, T3 y T4 (1,25 ± 0,15 vs. 1,85 ± 0,15 vs. 2,44 ± 0,16 cuerpos lúteos) y en TG entre T1 y T2 vs. T3 y T4. No hubo diferencias (P0,05) entre tratamien- tos en IE, NFP, DFP y DCL. En conclusión, la aplicación de 3 y 4 mL de LFE afectó TIE, TO y TG.

El consumidor es uno de los eslabones de la cadena de alimentos, responsable de mantener la inocuidad de los alimentos y evitar enfermedades por contaminación de los mismos. El objetivo del estudio fue determinar el nivel de conocimiento, actitud y comportamiento respecto a la inocuidad de los alimentos entre estudiantes universitarios, mediante la aplicación de un cuestionario a 97 estudiantes en el último tercio de la carrera profesional. La información se analizó mediante Ji-cuadrado. La inocuidad de los alimentos fue un tema de mediano interés entre otros temas de la vida diaria; sin embargo, la inocuidad fue la característica calificada como más importante de los alimentos y señalando mayoritariamente a los productos pecuarios como los de mayor riesgo de ocasionar enfermedades. La educación formal universitaria, internet y libros especializados fueron las fuentes principales de información sobre el tema de inocuidad. Se concluyó que para la industria pecuaria, la difusión hacia los consumidores de buenas prácticas sanitarias en el manejo de los alimentos es de interés para fomentar y disminuir la caída en el consumo de sus productos

This research studies the characteristics of the Mexican pork sector; adoption status of quality management systems, and product destinations. Ninety six percent of fifty enterprises have fully answered a questionnaire. Ninety percent are small and medium-sized, the rest are large-sized firms. Nineteen percent of them have totally adopted HACCP, sixty three percent are implementing or planning to do it, the rest have no plans to adopt it. Thirteen percent of the enterprises had ISO 9000. Thirty four percent of their sales go to supermarkets, 57% to other retail chains and 9% to exportation. Product destinations are mainly Central America, United States of America, Asia and Mexico. To improve efficiency and the quality of process it is necessary to implement HACCP. Besides, customers and legal requirements are the external factors, which result in this adoption. In the process of implementing, there are some problems, such as staff motivation and training. The results suggest that HACCP system operating is important for the Mexican pork industry. It also has relevant implications in domestic trade. It is necessary to encourage adoption of quality management systems in the sector.

Food marketing at international and domestic markets has focused on processing systems that improve food safety. The objective of this research is to determine the factors influencing the implementation of the HACCP system in the Mexican meat industry, and to identify the main marketing destination of their products. Only 18.5% of enterprises reports fully operational HACCP in their plants. The main destination of their production in the domestic market is supermarkets, suppliers and distributors and specific niches of the domestic market. Exports are to USA, Japan, Korea and Central America and some niches of the domestic market with requirements of higher quality. The four principal factors that motivate enterprises to adopt HACCP are associated with improvement of plant efficiency and profitability, adoption of good practices, improvement of product quality and waste reduction. It is concluded that Mexican enterprises adopt HACCP to successfully remain and face competition by foreign enterprises in the domestic market and to a lesser extent to compete in the international market.

Hazard Analysis and Critical Control Point (HACCP) is a safety and quality management tool used as major issue in international and domestic trade in food industry. However, detailed information on costs and benefits of HACCP implementation is needed to provide appropriate advice to food processing plants. This paper reports on the perceptions of costs and benefits by the Mexican poultry processing plants and sale destinations. The results suggest that the major costs of implementing and operating HACCP within poultry processing plants are record keeping and external technical advice. The main benefit indicated by the majority of processing plants is a reduction in microbial counts. Over 39% of poultry production is sent to nation-wide chains of supermarkets, and less than 13% is sent to international markets. It was concluded that the adoption of HACCP by the Mexican poultry processing sector is based on the concern to increase and keep the domestic market, rather than to compete in the international market.

El objetivo de este estudio fue determinar la fluctuación estacional de la población de Haematobia irritans (L.) en una zona templada de México; la población se registró a través de conteos semanales en vacas Holstein en pastoreo del 6 de septiembre de 1997 al 29 de agosto de 1998. Se correlacionaron los conteos de moscas con siete variables climáticas para las cuatro semanas previas a los conteos. Se detectó un número mayor a dos moscas por vaca a lo largo del año, con excepción de la segunda y tercera semana de enero. Las moscas adultas nunca desaparecieron de las vacas, indicando que si la diapausa ocurre en esta latitud, no afecta a toda la población de moscas. El mayor nivel de abundancia (392 moscas/vaca) se registró en mayo de 1998. La población de moscas se redujo entre el 15 de noviembre de 1997 y el 3 de enero de 1998, y aumentó entre el 14 de marzo y el 23 de mayo de 1998. La variable climática que mejor se correlacionó con los conteos de moscas fue la temperatura mínima a la intemperie (r=0,76). El número de moscas del cuerno se correlacionó mejor con los datos climáticos de la semana previa a los conteos. Se puede concluir que en esta zona del altiplano mexicano se puede registrar valores altos en la población de esta plaga, mientras que la mejor variable climática en la predicción de cambios en la población de la mosca del cuerno podría ser la temperatura mínima a la intemperie, con un valor límite de 0°C

"El objetivo del estudio fue determinar la susceptibilidad de Haematobia irritans (L.) a los insecticidas por medio de una prueba in vitro permetrina (2.5 y 6.0 µg/cm2) y diazinón (0.01 y 0.06 µg/cm2). Las moscas se recolectaron en 14 ranchos dedicados a la producción de bovinos productores de carne. También se realizó un estudio detallado por encuesta del tipo de manejo de los pesticidas al norte de Veracruz (México) durante 1998 y 2000 y la parte central de Nuevo León (México) en 2000. Para valorar el porcentaje de mortalidad de la mosca del cuerno se utilizaron bioensayos con dos dosis discriminantes de permetrina o diazinón, impregnados en frascos. Las moscas del cuerno fueron recolectadas en el campo directamente de los bovinos y expuestas inmediatamente a permetrina y diazinón. La mortalidad de las moscas se registró hasta no más de dos horas. Los resultados mostraron que el porcentaje de mortalidad para permetrina en Nuevo León y Veracruz fue poco signifi cativo e inexistente, respectivamente. En contraste, el porcentaje de mortalidad exhibido para diazinón fue más alto (P < 0.05) en ambas áreas experimentales. Sin embargo, el porcentaje de mortalidad disminuyó en Veracruz de un año a otro. La aplicación de una encuesta a través de cuestionarios sobre el uso de éstos y otros pesticidas también reveló que los organofosforados fueron los más utilizados para el control de esta plaga en Nuevo León, mientras que los piretroides fueron los más utilizados en Veracruz. La encuesta reveló que la inefi ciencia de los productos fue la razón principal para el cambio del grupo químico. La aplicación por aspersión fue el método más generalizado en los tratamientos a los bovinos en ambos estados. En la mayoría de los casos (86.7%), los ganaderos y veterinarios aplicaron más de diez tratamientos durante todo el año. Este estudio permite concluir que existe una resistencia generalizada a permetrina en los ranchos evaluados en los dos estados y que las poblaciones de la mosca del cuerno no mostraron resistencia al diazinón en ninguna de las áreas de trabajo."

En 1999, bajo condiciones controladas en campo, se evaluó la eficacia de los aretes con diazinón al 21.4% (un arete por bovino) y de ivermectina inyectable al 1% (1 ml/50 kg de peso, equivalente a 200 µg/kg) para el control de la mosca del cuerno en una unidad de producción para ganado bovino en Tuxpan, Veracruz, Mexico durante tres meses. En virtud de que existieron diferencias sustanciales en las condiciones de los dos potreros usados en cuanto a su capacidad para proveer de forraje a los bovinos, no se consideró posible la comparación directa de la variable de ganancia de peso para cada uno de los tratamientos entre sí y con el grupo testigo. Los conteos de moscas se realizaron cada diez días. Los aretes con diazinón al 21.4% proporcionaron un control equivalente a 87% sólo los días de observación 30, 50, 60, 70 y 90. Mientras que la aplicación de ivermectina logró un control 90% los mismos días. No se registró diferencia estadística significativa en eficacia entre los dos ectoparasiticidas.